共查询到20条相似文献，搜索用时 15 毫秒
1.
Yu. G. Chendev A. L. Aleksandrovskii O. S. Khokhlova L. G. Smirnova L. L. Novykh A. V. Dolgikh 《Eurasian Soil Science》2011,44(1):1-12
A sequence of dark gray forest soils developing under a virgin broadleaved forest and under croplands used for 100 and 150
years was studied in the southern part of the forest-steppe zone on the Central Russian Upland. The application of multiple
study methods for these objects made it possible to trace the evolutionary changes in the soil properties during the 150-year-long
period of regular plowing. Several important trends in the soil development under the impact of the cultivation were revealed:
(a) an increase in the thickness of the humus layer (according to the measurements at 20 points for each of the objects),
(b) an increase in the amount of mole tunnels, (c) a decrease in the coefficient of the textural differentiation of the soil
profile (with respect to the clay content), (d) an increase in the contents and reserves of the major nutrients upon a stable
pool of humus in the upper meter, and (e) some alkalization and carbonization of the profile. Powdery accumulations of carbonates
and whitish calcareous coatings on the faces of prismatic peds appeared at a depth of more than 130 cm. The plowed soils contained
thin deep fissures, the surface of which was covered by dark-colored clayey-humus coatings at the depth of 50–110 cm. The
radiocarbon age of the humus in these coatings was 500–1000 years younger than the age of the humus in the soil mass between
the fissures. This set of features attests to the evolution of the plowed dark gray forest soils into chernozems under the
impact of plowing. 相似文献
2.
E. S. Bukhanistova T. A. Gorelova A. A. Tanasienko A. S. Chumbaev 《Eurasian Soil Science》2006,39(6):622-630
It is shown that humus loss may reach 1.7 t/ha per year as a result of plowing of leached chernozems and erosion development. Distribution of underground phytomass in uneroded and eroded chernozems and slightly aggraded meadow-chernozemic soils of dissected areas in the Cis-Salair region is analyzed. It is shown that an increase in the degree of soil erosion is accompanied by a decrease in the total phytomass reserves, whereas the average depth of the root zone increases. 相似文献
3.
Humic acids (HAs) in the noncalcareous chernozems developed from the colluvium of argillites and chlorite schist are characterized by a predominance of the first, relatively mobile fraction (HA-1) and a lower content of the second (HA-2) fraction. Modern nondestructive physicochemical methods for studying the chemical structure of HA macromolecules have shown that the Has in the virgin soils have approximately equal portions of aromatic and aliphatic groups. In the plowed soils, the portion of aromatic carbon increases under the impact of the intensive agricultural use of these soils and their susceptibility to wind erosion. 相似文献
4.
The humus state of rainfed chernozems affected by local waterlogging was studied. The total humus content in the hydromorphic
chernozems increases, as well as the content of fulvic acids, whereas the content of nonhydrolyzable residue (humin) decreases.
A significant increase in the portions of the third fractions of humic and fulvic acids is observed. The role of the fine
silt and clay fractions in the binding of humic substances increases in the lower horizons of locally hydromorphic soils.
The increase in the content of fulvic acids (fulvatization) is mainly due to their predominance in the clay fraction. The
latter is specified by the significant narrowing of the Cha-to-Cfa ratio, the lower content of the nonhydrolyzable residue, and the increased content of the clay-bound (3rd fraction) fulvic
and humic acids. The composition of the humus in the fine silt fraction of the studied soils is characterized by an increased
amount of humic acids of the second fraction with a decrease in the relative content of fulvic acids. 相似文献
5.
The contents of free radicals in preparations of humic and fulvic acids extracted from virgin and plowed podzolic, surface gleyic podzolic, and peaty podzolic-gleyic soils were determined. The concentration of paramagnetic centers in the humic acids was 1.5–2 times higher than that in the fulvic acids. The agricultural use decreases the paramagnetic activity of the humus compounds and promotes the accumulation of biothermodynamically stable organic compounds in the plow horizons. 相似文献
6.
V. M. Semenov L. A. Ivannikova T. V. Kuznetsova N. A. Semenova A. S. Tulina 《Eurasian Soil Science》2008,41(7):717-730
The susceptibility of soil organic matter (SOM) to mineralization decreases in the following sequence of zonal soils: tundra soil > soddy-podzolic soil > gray forest soil > chestnut soil > dark chestnut soil > chernozem. The content of potentially mineralizable organic matter in the plowed soils is 1.9–3.9 times lower than that in their virgin analogues. The highest soil carbon sequestration capacity (SCSC) is typical of the leached chernozems, and the lowest SCSC is typical of the tundra soil. Taking into account the real soil temperatures and the duration of the warm season, the SCSC values decrease in the following sequence: leached chernozem > dark chestnut soil > chestnut soil ≥ tundra soil > gray forest soil > soddy-podzolic soil. Arable soils are characterized by higher SCSC values in comparison with their virgin analogues. 相似文献
7.
Data on radiocarbon ages of different fractions of humus (humic acids, fulvic acids, and humin) in the profiles of chernozems
are analyzed. A chronoecological grouping of humus in modern and buried (fossil) soils is suggested. An increase in the radiocarbon
age of humic substances down the soil profile has a stepwise character. It is shown that the 14C content in chernozems decreases down the soil profile more somewhat slower than the 12C content. The dependence of a decrease in the humus content of buried soils on the age of burying is traced for a time span
of 800 ka. 相似文献
8.
A. S. Vladychenskii L. S. Malyukova N. V. Kozlova 《Moscow University Soil Science Bulletin》2007,62(4):175-181
Changes in the humus status of acid brown forest soils used for tea growing have been studied in a long-term stationary experiment after 20 years of the application of mineral fertilizers in increasing doses. It is shown that long-term tea growing has resulted in a reliable increase in the humus content within the upper cultivated horizon (Ap, 0–40 cm) at the expense of the nonhydrolyzable fraction of humus (humin) and the first fractions of humic and fulvic acids. The fractional composition of humus has changed against the background of a stable fulvate type of humus (Cha/Cfa < 0.5). The portion of the first fraction of humic and fulvic acids in the total amount of humus has increased, as well as the portion of the first fraction of humic acids in the total amount of humic acids. These changes are due to the enhanced humification of plant residues with a parallel decrease in the contents of the second (Ca-bound) and third (bound with clay and stable sesquioxides) fractions of humic substances. 相似文献
9.
L. P. Galeeva 《Eurasian Soil Science》2012,45(2):206-219
The trends of the soil-forming process and the changes in the main physicochemical properties of leached chernozems under
different phytocenoses (virgin land, cereal-row crop rotation, and sown perennial grasses (Galega + Bromopsis)) were studied. In the cereal-row crop agrocenoses, as compared to the virgin land, the thickness of the humus horizon increased,
and the depth of effervescence remained the same. The reaction of the leached chernozems in the phytocenoses did not change,
and the sum of exchangeable bases increased in the following sequence: sown perennial grasses < cropland = virgin land. The
humus content and its reserves in the 0- to 20-cm soil layer of all the agrophytocenoses were almost the same, and the total
nitrogen content decreased in the following sequence: virgin land = cropland > perennial grasses. On the contrary, the total
phosphorus content, its mobility, the phosphorus capacity and reserves, and the sum of the mineral phosphates increased in
the same order. The highest content of exchangeable potassium was found in the soils of the virgin land and the lowest one,
in the soils of the cereal-row crop agrocenosis. The perennial grasses consumed the greatest amounts of potassium and nitrogen
and the spring wheat of the cereal-row crop rotation, those of nitrogen. The removal of nitrogen was 1.6–1.8 and 2.3 times
greater than the losses of phosphorus and potassium, respectively. 相似文献
10.
The humus status and CO2 production have been assessed in soils of natural and anthropogenic landscapes in southern regions of the Far East with different types of redox conditions. A higher production of CO2 is typical of burozems and soddy-eluvial-metamorphic soils with oxidative and contrast redox conditions. These are soils with medium or high humus content, high potential humification capacity, and medium enrichment with catalase. A decrease in the content of humus in the plow horizons of soils in agrogenic landscapes is revealed compared to their natural analogues. The studied soils mainly have humus of the fulvate–humate type. The fractions strongly bound to the mineral soil component prevail in humic acids. In waterlogged mucky-humus gley soils, the anaerobic conditions hamper the biological activity and transformation of organic matter, which favors its accumulation. A low production of CO2 is observed in soils with reducing conditions. To determine the differences between the CO2 emission parameters in soils of agrogenic and natural landscapes, monitoring studies should be extended. 相似文献
11.
Differentiation of Kamchatka soils with respect to the composition and pools of humus is discussed. Very low and low pools of humus of the fulvate type are typical of the ocherous and stratified ocherous volcanic soils of the eastern coastal zone and the Central Kamchatka Depression. Ocherous volcanic soils of the Western Kamchatka Lowland are characterized by the low and moderate pools of the humate–fulvate humus. Agrogenic soils are characterized by the higher pools of humus in the upper 20 cm in comparison with their natural analogues, which is largely related to changes in the physical properties of the soils under the impact of tillage. 相似文献
12.
M. F. Ovchinnikova 《Eurasian Soil Science》2016,49(8):859-867
The transformation of humus substances resulting from artificial drainage of the surface-gleyed soddy-podzolic soils under conditions of pronounced microtopography and different agrogenic loads was studied. The studied soil characteristics included acid–base conditions, the content and group composition of humus, the ratios between the fractions of humus acids, and optical density of humic acids. The features attesting to humus degradation were found in the soils of microdepressions periodically subjected to excessive surface moistening, in the soils of different landforms upon the construction of drainage trenches, and in the plowed non-fertilized soils. The response of humus characteristics to the changes in the ecological situation in the period of active application of agrochemicals for reclamation of the agrotechnogenically disturbed soils was traced. It was shown that the long-term dynamics of the particular parameters of the biological productivity of the soil depend on the hydrological and agrogenic factors, as well as on the weather conditions. 相似文献
13.
The effect of lime and organic and mineral fertilizers on the fractional and group composition of the humus in a light loamy
soddy-podzolic soil was studied in a long-term experiment. The application of lime increased the content of the agronomically
valuable fraction of humic acids (HA-2) by 2.6 times on the average. The application of mineral fertilizers at the rate of
N83P61K112 (kg/ha per year) increased the mobility of the humic substances; the application of farmyard manure (12.5 t/ha
per) has an opposite effect. In general, various fertilizer systems exerted a favorable effect on the qualitative composition
of the humus with an increase in the percentage of humic acids, though the humate-fulvate type of humus was preserved in all
the variants of the experiment. 相似文献
14.
I. M. Gabbasova R. R. Suleymanov I. K. Khabirov M. A. Komissarov T. T. Garipov L. V. Sidorova F. I. Nazyrova 《Eurasian Soil Science》2014,47(2):35-46
The soil cover of Tra-Tau and Yurak-Tau shikhans (monadnocks) has been examined. Leached and typical medium-deep chernozems are developed on colluvial fans on the footslopes and on the lower parts of slopes, whereas typical calcareous thin slightly and moderately gravelly chernozems are developed on the upper and medium parts of slopes. The leached and typical chernozems of the footslopes correspond to zonal soils of the adjacent plain areas, though they have some specific features related to the local topographic conditions. These soils are somewhat thinner than plain chernozems and are characterized by the perfect granular water-stable structure, the high content of humus of the humate type, the high content of exchangeable cations, strong acid-base buffering, and high enzymatic activity. These features predetermine their high tolerance towards technogenic impacts. The concentrations of highly hazardous substances of the first toxicity class (mercury, arsenic, lead, and cadmium) and of moderately hazardous substances of the second toxicity class (copper, zinc, and nickel), as well as the concentrations of low-hazardous elements (manganese and iron) in these soils do not exceed provisional maximum permissible concentrations of these substances in soils irrespectively of the slope aspect. No changes in the physicochemical and biological properties of the soils under the impact of technogenic loads from Sterlitamak industrial center have been identified. 相似文献
15.
S. V. Lukin 《Eurasian Soil Science》2017,50(11):1323-1331
Data of the agrochemical survey of arable soils in Belgorod oblast during the period from 1964 to 2014 have been analyzed. The soil cover mainly consists of typical chernozems (Haplic Chernozems) and leached chernozems (Luvic Chernozems) in the forest-steppe zone and ordinary chernozems (Calcic Chernozems) in the steppe zone. Under long-term agricultural use (from 1964 to 2014), the content of mobile phosphorus in arable soils of the region under study has increased from 55 to 137 mg/kg, and the content of mobile potassium has increased from 105 to 147 mg/kg. During the period of 1976–2014, the share of acid soils has increased from 22.8 to 45.8%, including medium-acid soils from 1.5 to 12.6%. No significant changes in the weighted average content of soil organic matter are revealed for the period from 1985 to 2014. The value of this parameter is within the range of 4.8–5.0%. In the 2010–2014, 95.0% of arable soils belonged to the category of low supplied with mobile sulfur; 99.2, 96.9, 94.1, and 54.4% of soils were poorly supplied with zinc, copper, cobalt, and manganese, respectively. During the same period, the maximum average productivity of the crop area (3710 f. u./ha) was noted at the application of 4.8 t/ha organic fertilizers and 97.9 kg/ha organic fertilizers on the average. The maximum long-term yields of sugar beet (36.8 t/ha) and corn grain (4.97 t/ha) were obtained at the application of relatively low fertilizer rates. 相似文献
16.
Periodical forest fires are typical natural events under the environmental and climatic conditions of central and southern Yakutia and Transbaikal region of Russia. Strong surface fires activate exogenous geomorphological processes. As a result, soils with polycyclic profiles are developed in the trans-accumulative landscape positions. These soils are specified by the presence of two–three buried humus horizons with abundant charcoal under the modern humus horizon. This indicates that these soils have been subjected to two–three cycles of zonal pedogenesis during their development. The buried pyrogenic humus horizons accumulate are enriched in humus; nitrogen; total and oxalate-extractable iron; exchangeable bases (Са+2 and Mg+2); and the fractions of coarse silt, physical clay (<0.01 mm), and clay (<0.001 mm) particles in comparison with the neighboring mineral horizons of the soil profile. The humus of buried pyrogenic horizons is characterized by the increased content of humic acids, particularly, those bound with mobile sesquioxides (HA-1) and calcium (HA-2) and by certain changes in the type of humus. 相似文献
17.
The biological activity of soil samples taken from genetic horizons of plowed and virgin chernozems in the Kamennaya Steppe Reserve was determined as the amount evolved from the soil upon its incubation in laboratory conditions. In the top humus horizons, the biological activity of virgin chernozem was two to three times higher as compared with that in the plowed chernozem. The intensity of biological processes and the microbial biomass in the soil profile was mainly controlled by the quantity and quality of soil organic matter. Long-term agricultural use exerted a weaker effect on the biological properties of chernozems developed on microelevations (blocks) of the paleocryogenic microtopography in comparison with chernozems developed in the microdepressions between the blocks. The factor analysis showed that soil characteristics related to the biological processes comprise more than 50% of the total variance of factor loads and are distinctly differentiated in the soil profile. 相似文献
18.
The phenomenon of mineralization (biological mineralization) of organic matter in chernozems has been studied. A decrease
in the content of Corg with time can be considered an index of the organic matter mineralization. It is suggested that the humus horizons of modern
chernozems contain the pools of organic matter of different ages: easily decomposable organic matter, labile biologically
active humus, stable biologically active humus, and relatively inert humus. The composition and mean residence times of these
pools and their contribution to the total organic matter content have been estimated. The particular types of the biological
mineralization have been determined on the basis of the comparison between the velocities of mineralization (M) and humification
(H) processes: total unidirectional mineralization (M ≫ H), equilibrium mineralization (M ∼ H), nonequilibrium mineralization
(M> <H), and zero mineralization. The separation of subtypes is based on data on the relative rates (%) of the organic matter
mineralization. On the basis of available experimental data on chernozems buried under kurgans and in loess sediments (with
the age of up to 800 ka), the quantitative relationship of the humus content in the buried soils on their age has been found;
it has an exponential shape. During the first 100 ka after the soil burial, the soil humus content gradually (with a slowing
intensity) decreases from 100–75 to 6.5% of its content in the virgin chernozems. Then, 100–1000 ka after the soil burial,
the soil humus content remains approximately constant (6.5% of the initial level, or 0.3% of the soil mass). The rates of
mineralization have been estimated. It is shown that the elemental composition (C, H, N, O) of humic acids remains relatively
stable for a long time due to the regeneration of the chemical structure of humus (matric restoration of humus). It is suggested
that several different forms of humus related to pedogenesis should be distinguished in the biosphere. The renewable humus
in the equilibrium state with the environment is typical of the open biospheric (soil) systems. The fossil humus, whose content
decreases with time, and whose composition remains stable, is typical of the semiclosed and closed systems. With time, it
transforms into residual humus, whose content and composition remain stable. The fossilized organic matter in the fossil soils
and sediments of the past geological epochs (Mesozoic and Paleozoic) considerably differs from the renewable, fossil, and
residual humus. 相似文献
19.
The physicochemical conditions and morphological features of solonetzic process in soils of chernozemic solonetzic complexes
were studied in the area of solonetzic experimental station no. 1 in the Kamennaya Steppe area in 55 years after a single
application of ameliorative measures (earthening, gypsuming, and manuring) and cessation of the annual plowing. It was found
that the modern soil-forming factors favor the development of soil processes inherent in native chernozems and solonetzes
prior to their plowing and amelioration. They cause the restoration of the humus horizon in chernozems and the morphological
differentiation of solonetzes after the cessation of plowing. Active postameliorative and postagrogenic restoration of solonetzic
features is related to the preservation of the physicochemical conditions (the low concentration of salts and the presence
of exchangeable sodium) in the soil profile. The humus horizon of chernozems applied over the surface of solonetzes is characterized
by the appearance of solonetzic features under hydromorphic conditions. 相似文献
20.
The composition of humus in leached chernozems differs from that in gleyed podzolized chernozem-like soils in the northern forest-steppe zone of European Russia. Leached chernozems have the fulvate-humate humus. Gleyed podzolized chernozem-like soils have the humate-fulvate humus. A more aggressive composition of humus in the latter soils is caused by their overwetting and the development of gley processes under conditions of a stagnant-percolative soil water regime. 相似文献